No, you find t0 since from the Earth's frame of reference (ie. tv) it will take the however many years given in the question for the spacecraft to reach its destination, where as the spacecraft measures less time to get to the destination.Don't we find tv??? I find tv
Isn't because if u are moving at fast constant speed, it can also means the space moving at that speed in relative to you too.... :S
Such an easy mark or so, I can't believe I had a memory blank about this!!!